Abstract: Disclosed is a method for producing a nylon salt powder, wherein in the production of a nylon salt powder by allowing a dicarboxylic acid powder to react, the content of water is regulated to be 5% by mass or less in relation to the total amount of the dicarboxylic acid powder and a diamine, the dicarboxylic acid powder is beforehand heated to a temperature equal to or higher than melting point of the diamine and equal to or lower than the melting point of the dicarboxylic acid, and while this heating temperature is being maintained, the diamine is added to the dicarboxylic acid powder in such a way that the dicarboxylic acid powder maintains the condition of being in powder form.

Abstract: Methods and systems for preparing catalyst, such as chromium catalysts, are provided. The valence of at least a portion of the catalyst sent to an activator is changed from Cr(III) to Cr(VI). The catalyst is prepared or activated continuously using a fluidization bed catalyst activator.

Abstract: A process for preventing or reducing polymer agglomeration and/or accumulation on or around the gas distribution grid in an olefin polymerization, fluidized-bed reactor. The process involves introducing one or more scouring balls into the reactor above the gas distribution grid, and carrying out olefin polymerization in the presence of the scouring balls. Also disclosed is a process for polymerizing olefins in a fluidized-bed reactor with reduced polymer agglomeration and/or accumulation on the gas distribution grid.

Abstract: A method for preventing or reducing agglomeration and/or accumulation on or around the gas distribution grid in a fluidized-bed vessel. The method involves introducing one or more scouring balls into the vessel above the gas distribution grid, and carrying out a fluidized-bed process in the presence of the scouring balls.

Abstract: An improvement to the phase interface process of preparing aromatic polycarbonate is disclosed. The process is characterized in that the phosgenation is carried out at 0 to 40° C., and in that the temperature of the reaction mixture at the time of addition of the catalyst at 10 to 40° C., and in that the molar ratio of aromatic dihydroxy compounds to phosgene at 1:1.05 to 1:1.20. The polycarbonate thus produced is characterized in its low content of carbamates, making it particularly suitable for the preparation of optical storage media.

Abstract: A polymerization reactor having at least three side wall surfaces and a bottom wall surface forming a reservoir and at least one heat exchanger plate in fluid communication with a coolant source, wherein each of the at least one heat exchanger plate is disposed on a lid. The polymerization reactors of the present invention permit large amounts of polymer to be formed in each reactor batch. Preferably, polymers are formed in the polymerization reactor by bulk polymerization. Methods for forming polymers is also disclosed.

Abstract: Organopolysiloxanes having aminoalkyl groups are prepared by (i) reacting (A) linear, cyclic or branched organopolysiloxanes with (B) aminoalkylsilanes which have an SiC-bonded, basic nitrogen-containing hydrocarbon radical and 2 or 3 hydrolyzable groups, ?or the partial or complete hydrolysis products thereof, optionally in the presence of (C) basic catalysts and/or (D) chain-terminating reagents, and (ii) optionally, after the reaction (i) neutralizing the optionally used basic catalysts (c), with the proviso that compounds (A), (B) and, when used, (D) are reacted continuously in a reaction space whose ratio of length to diameter is equal to or greater than four.

Abstract: In some embodiments, a method including the steps of: during a polymerization reaction producing a polymer resin in a fluid bed reactor, measuring reaction parameters including at least reactor temperature, at least one property of the resin, and amount of at least one condensable diluent gas in the reactor; determining from at least one measured resin property using a predetermined correlation, a dry melt initiation temperature value for a dry version of the polymer resin; and during the reaction, using a melt initiation temperature depression model to determine in on-line fashion a reduced melt initiation temperature for the resin (e.g., a temperature at which the resin is expected to begin to melt) in the presence of the at least one condensable diluent gas in the reactor.

Abstract: A process for continuously producing a polymer drag reducing agent (DRA) is described. The process concerns mixing a monomer and a catalyst in at least one continuously stirred tank reactor (CSTR) to form a mixture. The mixture is continuously injected into a volume continuously formed by a thermoplastic material, such as polyethylene. The thermoplastic material is periodically sealed off to form a temporary container or bag. The monomer is permitted to polymerize in the temporary container to form polymer. In one non-limiting embodiment, the polymerization in the bag takes place within an inert, circulating fluid that accelerates heat transfer. The polymer and the temporary container are then ground together, preferably at non-cryogenic temperatures, to produce a particulate polymer drag reducing agent. In one preferred, non-limiting embodiment, the grinding or pulverizing occurs in the presence of at least one solid organic grinding aid.

Abstract: The extremely rapid anionic polymerization rate of polystyrene has made polymerization difficult to control and has prevented large-scale development. This invention uses batch polymerization to utilize the rapid rate of polymerization to complete polymerization from zero to 100% conversion in minutes and turns this rapid rate into an advantage. Polystyrene itself is used as a heat sink to limit and control the maximum temperature reached during polymerization. Adiabatic polymerization increases the polymer temperature to the desired processing temperature of the polymer for either removal of volatile compounds or for direct pellet formation when no solvent is employed. The polystyrene to be used as a heat sink is added either as pellets or is first formed at a low controllable temperature. Extremely low levels of residual monomer are found in the product. This invention also demonstrates techniques to prevent gel formation or to reduce formation to an acceptable level.

Abstract: A process is provided for producing a vinyl chloride-based polymer by polymerization of vinyl chloride or a monomer mixture containing it in a reaction vessel. Heat generated during polymerization is removed using a reflux condenser. When the polymerization rate is within a range from 30% to 50%, a copolymeric polyether, with a weight average molecular weight of 1,500,000 to 2,000,000, and an ethylene oxide to propylene oxide molar ratio within a range from 78/22 to 82/18, is added to the reaction mass. Foaming of the polymer slurry due to the use of the reflux condenser beyond the point where the polymerization rate reaches 60% is suppressed, and the polymer can be produced with no deleterious effects on the quality of the product polymer.

Abstract: A process of producing a polymer by aqueous solution polymerization with good productivity without causing the formation of noxious gases or the formation of impurities due to the noxious gases, or without any danger of foaming and the like is disclosed. The process includes subjecting a monomer to aqueous solution polymerization while controlling the temperature using at least one device of an external circulation device and an internal coil device each having heat exchanging function.

Abstract: The present invention provides such a production process that a low-cost water-absorbent resin having excellent quality can be obtained by reasonable steps in aqueous solution polymerization. The production process for a water-absorbent resin comprises a polymerization setup that includes the steps of: supplying an aqueous solution of a water-soluble unsaturated monomer component including a major proportion of acrylic acid and/or its salt into a polymerization vessel causing shearing action; and then carrying out polymerization, involving crosslinking, of the water-soluble unsaturated monomer and at the same time carrying out fine division of the resultant hydrogel; with the production process being characterized in that the aqueous solution of the water-soluble unsaturated monomer component as supplied into the polymerization vessel has a temperature of not lower than 40° C.

Abstract: The present invention relates to a process for the gas-phase (co-)polymerisation of olefins in a fluidised bed reactor wherein fouling is prevented and/or flowability of polymer is improved thanks to the use of a process aid additive.

Abstract: Methods for controlling the temperature of an olefin polymerization reactor (e.g., a polyethylene reactor) system are disclosed herein. The olefin polymerization reactor system includes a polymerization reactor and a cooling jacket in thermal contact with the reactor. An aqueous froth is present in the jacket, and the pressure therein is maintained below atmospheric pressure. Control of the pressure in the jacket controls the boiling temperature of the jacket fluid, and thus, controls the rate of heat transfer from the reactor to the fluid in the jacket. This provides an efficient and simple means for controlling the reactor temperature.

Abstract: A method for end-capping polycarbonate resins, comprising the step of processing a mixture comprising a polycarbonate having free hydroxyl-end groups and an end-capping reagent in a melt transesterification reaction to produce a polycarbonate resin, wherein the end-capping reagent comprises a mixture of: (a) at least one species of a symmetrical activated aromatic carbonate, and (b) at least one species of an optionally-substituted phenol, whereby said end-capping reagent reacts with at least some of the free hydroxyl end-groups of the polycarbonate to produce an end-capped polycarbonate resin.

Abstract: A process for the production of polycarbonate is disclosed. The process, representing an improvement over the known interfacial polycondensation process entails introducing into the loop of a circulating reactor that additionally contains, a residence tank, an optional mixer, a pump, and a heat exchanger (i) an organic phase that contains a solvent for polycarbonate and phosgene and (ii) an aqueous phase that contains an aqueous lye solution, a dihydroxy compound and an optional monophenol to form an emulsion. Maintaining specified temperature and process conditions results in polycarbonate resin having good properties and in waste water that are characterized by their purity.

Abstract: Processes for the living polymerization of olefin monomers with terminal carbon-carbon double bonds are disclosed. The processes employ initiators that include a metal atom and a ligand having two group 15 atoms and a group 16 atom or three group 15 atoms. The ligand is bonded to the metal atom through two anionic or covalent bonds and a dative bond. The initiators are particularly stable under reaction conditions in the absence of olefin monomer. The processes provide polymers having low polydispersities, especially block copolymers having low polydispersities. It is an additional advantage of these processes that, during block copolymer synthesis, a relatively small amount of homopolymer is formed.

Abstract: The invention relates to cholesteric polymer flakes obtainable from a chiral polymerizable mesogenic material, to methods of manufacturing such cholesteric flakes, to the use of certain chiral and achiral polymerizable compounds with one or more terminal polymerizable groups for the manufacturing of such flakes and to the use of such cholesteric flakes as effect pigments in spraying or printing inks or paints or colored plastics for different applications, especially for automotive use, cosmetic products and security applications.

Abstract: The invention relates to cholesteric polymer flakes obtainable from a chiral polymerizable mesogenic material, to methods of manufacturing such cholesteric flakes, to the use of certain chiral and achiral polymerizable compounds with one or more terminal polymerizable groups for the manufacturing of such flakes and to the use of such cholesteric flakes as effect pigments in spraying or printing inks or paints or colored plastics for different applications, especially for automotive use, cosmetic products and security applications.

Abstract: A method for producing a water absorbent resin by polymerizing a water-soluble monomer having a polymerizable unsaturated group (A) and a crosslinking agent (B) as the essential components by radical polymerization in the presence of water or, polymerizing a water-soluble monomer having an unsaturated group (A) and a crosslinking agent (B) by radical-graft copolymerization with a water-soluble polymer (C) as the backbone polymer in the presence of water, wherein a water-based solid material capable of being endothermally fused or dissolved into water (D) is added when initiating the polymerization, with at least a part of the water-based solid material (D) in a solid state. By the method of the present invention, a water absorbent resin having a high molecular weight and a high absorption capacity with little water-soluble component can be obtained with ease.

Abstract: A method for producing a water absorbent resin by polymerizing a water-soluble monomer having a polymerizable unsaturated group (A) and a crosslinking agent (B) as the essential components by radical polymerization in the presence of water or, polymerizing a water-soluble monomer having an unsaturated group (A) and a crosslinking agent (B) by radical-graft copolymerization with a water-soluble polymer (C) as the backbone polymer in the presence of water, wherein a water-based solid material capable of being endothermally fused or dissolved into water (D) is added when initiating the polymerization, with at least a part of the water-based solid material (D) in a solid state. By the method of the present invention, a water absorbent resin having a high molecular weight and a high absorption capacity with little water-soluble component can be obtained with ease.

Abstract: There is provided a process comprising polymerizing a compound selected from the group consisting of a conjugated diene, a vinyl-substituted aromatic compound, and mixtures thereof in a gas phase fluidized polymerization vessel under polymerization conditions in the presence of at least one anionic initiator, optionally in the presence of an inert particulate material. A novel resin particle produced by the process is also provided.

Abstract: A process for (co)polymerizing alpha-olefins in the gas phase in a fluidized bed or mechanically stirred bed reactor using a Ziegler-Natta type catalyst or a heat activated chromium oxide/refractory oxide catalyst wherein the (co)polymerization is carried out in the presence of 0.005 to 0.2 weight %, based on the weight of the (co)polymer bed, of an inert pulverulent inorganic substance (e.g. silica) having a mean particle diameter between 0.5 and 20 microns. The process is capable of being operated at temperatures closer to the softening point of the produced polyolefin than in the absence of the pulverulent solid.

Abstract: A process for (co)polymerizing alpha-olefins in the gas phase in a fluidized bed or mechanically stirred bed reactor using a Ziegler-Natta type catalyst or a heat activated chromium oxide/refractory oxide catalyst wherein the (co)polymerization is carried out in the presence of 0.005 to 0.2 weight %, based on the weight of the (co)polymer bed, of an inert pulverulent inorganic substance (e.g. silica) having a mean particle diameter between 0.5 and 20 microns. The process is capable of being operated at temperatures closer to the softening point of the produced polyolefin than in the absence of the pulverulent solid.

Abstract: This invention concerns the production of 1,4-cis polybutadiene, or copolymers of butadiene with other related diolefins, through the catalytic polymerization or copolymerization of butadiene monomer by a continuous or discontinuous process carried out in the absence or substantial absence of solvents or diluents and operating in the presence of solid bodies.

Abstract: An exothermic gel polymerization process conducted in the presence of water is initiated at a low temperature, is held for most of the process at a higher temperature by including in the medium a particulate heat sink material, such as sodium sulphate decahydrate, that is substantially insoluble in the medium and which undergoes an endothermic phase change and is then allowed to rise to a higher temperature. Either as a result of the endothermic change, or as a result of a subsequent exothermic change, at the end of the process the heat sink material is again solid particulate material substantially insoluble in the medium and so the product is a dispersion of the material in a polymer gel. The polymer is water soluble.

Abstract: Polymers are prepared from a vinyl monomer or monomers by a homopolymerization or a copolymerization reaction which occurs exothermically, said reaction being carried out by mixing the vinyl monomer or monomers with an additive comprising an endothermic compound which is unreactive with said monomer or monomers and the resultant homopolymers or copolymers and has a phase transition point at the temperature of the polymerization reaction with the absorption of heat, the amount of said endothermic compound being sufficient to counterbalance the major part of the exothermic heat of reaction, the process being especially useful for preparing polymers in solid form or for preparing high solid suspensions of polymers.

Abstract: The invention relates to an improvement in the solid state polymerization of polyester prepolymer comprising the use of low molecular weight prepolymer having an intrinsic viscosity ranging from about 0.1 to about 0.35 and essentially in the form of discrete spherical beads.

Abstract: Polymers in powder form are manufactured by polymerizing water-soluble ethylenically unsaturated monomers, which form hydrophilic polymers, in a powder bed of polymers of water-soluble ethylenically unsaturated compounds in the presence of polymerization initiators and water as an auxiliary liquid, the water being entirely or partially removed from the polymerization zone by evaporation during the polymerization.

Abstract: Disclosed is a method of conducting under selected temperature conditions and with agitation a chemical operation which requires agitating a liquid phase under selected conditions, by enclosing the involved starting materials in a liquid-tightly enclosed cylindrical operating zone by a zone-enclosure that is a heat conductor and is of greater length than diameter and is enveloped by a subdivided temperature-control fluid-confining zone, and agitating the operating zone contents by rotating the operating zone with the fluid-confining zone while feeding temperature-control fluid through the temperature-control zone. Also enclosed is the apparatus that provides the cylindrical operating zone enveloped by the temperature-control zone.